Moderate CentOS libreswan Security Update


libreswan-3.12-10.1.el7_1.src.rpm, libreswan-3.12-10.1.el7_1.x86_64.rpm,
2018-01-18 11:10
2017-07-27 19:09
2017-04-01 19:09
2017-01-05 20:13


Updated libreswan packages that fix one security issue, several bugs and
add two enhancements are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having Moderate security
impact. A Common Vulnerability Scoring System (CVSS) base score, which
gives a detailed severity rating, is available from the CVE link in the
References section.

Libreswan is an implementation of IPsec & IKE for Linux. IPsec is the
Internet Protocol Security and uses strong cryptography to provide both
authentication and encryption services. These services allow you to build
secure tunnels through untrusted networks such as virtual private network

A flaw was discovered in the way Libreswan's IKE daemon processed certain
IKEv1 payloads. A remote attacker could send specially crafted IKEv1
payloads that, when processed, would lead to a denial of service (daemon
crash). (CVE-2015-3204)

Red Hat would like to thank Javantea for reporting this issue.

This update fixes the following bugs:

* Previously, the programs/pluto/state.h and
programs/pluto/kernel_netlink.c files had a maximum SELinux context size
of 257 and 1024 respectively. These restrictions set by libreswan limited
the size of the context that can be exchanged by pluto (the IPSec daemon)
when using a Labeled Internet Protocol Security (IPsec). The SElinux
labels for Labeled IPsec have been extended to 4096 bytes and the
mentioned restrictions no longer exist. (BZ#1198650)

* On some architectures, the kernel AES_GCM IPsec algorithm did not work
properly with acceleration drivers. On those kernels, some acceleration
modules are added to the modprobe blacklist. However, Libreswan was
ignoring this blacklist, leading to AES_GCM failures. This update adds
support for the module blacklist to the libreswan packages and thus
prevents the AES_GCM failures from occurring. (BZ#1208022)

* An IPv6 issue has been resolved that prevented ipv6-icmp Neighbour
Discovery from working properly once an IPsec tunnel is established (and
one endpoint reboots). When upgrading, ensure that /etc/ipsec.conf is
loading all /etc/ipsec.d/*conf files using the /etc/ipsec.conf "include"
statement, or explicitly include this new configuration file in
/etc/ipsec.conf. (BZ#1208023)

* A FIPS self-test prevented libreswan from properly starting in FIPS mode.
This bug has been fixed and libreswan now works in FIPS mode as expected.

In addition, this update adds the following enhancements:

* A new option "seedbits=" has been added to pre-seed the Network Security
Services (NSS) pseudo random number generator (PRNG) function with entropy
from the /dev/random file on startup. This option is disabled by default.
It can be enabled by setting the "seedbits=" option in the "config setup"
section in the /etc/ipsec.conf file. (BZ#1198649)

* The build process now runs a Cryptographic Algorithm Validation Program
(CAVP) certification test on the Internet Key Exchange version 1 and 2
(IKEv1 and IKEv2) PRF/PRF+ functions. (BZ#1213652)

All libreswan users are advised to upgrade to these updated packages,
which contain backported patches to correct these issues and add these
Please see

Am I vulnerable?

The constraints below list the versions that this vulnerability is patched in, and versions that are unaffected. If a patch is ready but unrealeased, then it is pending.

Or, you can just let us figure it out for you! Appcanary continously monitor your installed packages, and tell you if any of them are vulnerable.

Sign up for monitoring

Affected package information

Release Package Patched in
7 libreswan libreswan-3.12-10.1.el7_1.src.rpm
libreswan libreswan-3.12-10.1.el7_1.x86_64.rpm